Flexural behavior of precast lightweight aggregate concrete insulation panels

Abstract

This study examined the effect of different panel-to-base connection techniques on the flexural behavior of precast lightweight aggregate concrete (PLC) panels with an embedded honeycomb cardboard for lighter weight and better insulation performance. Eight full-size PLC insulation panels were prepared with test parameters including panel-to-base connection techniques, the compressive strength of concrete (fc′), and continuity of span. All panel specimens were tested under symmetrical two-point top loadings in each span. The test results revealed that the flexural design process specified in the code American Concrete Institute 318-19 commonly underestimated the flexural cracking and moment capacity of the PLC specimens. The PLC insulation panel specimens with an fc′ exceeding 13 MPa could be classified into grade 1 as specified in the code KS F 4736, indicating a good flexural resistance. For conservative flexural design of PLC insulation panels, the use of the conventional spliced connection and modified spliced sleeve connection could be considered as a fixed end, whereas the use of screw-bolt-and-spring connections could be considered as a hinged end. The displacement ductility ratios of PLC insulation panels with an fc′ of 24.5 MPa were approximately 1.2 times higher than those of the counterpart PLC insulation panels with an fc′ of 13 MPa, because more severe cracks along the insulation materials were observed in the specimens with lower fc′ values.